The 130-250F B-Series Mechanical Temperature Murphygage with 35 Ft Capillary 20BTG-250-35-1/2 is a high quality, diaphragm-actuated indicating gage. With the same heavy-duty design as the standard 20 series Swichgage, the B-gage is more compact and is the optimum instrument for gage-only applications. It has a high impact polycarbonate lens, sturdy steel case and a polished, low-profile stainless steel bezel. Accuracy and protection from moderate over-pressure/over-temperature are assured by a unique, unitized diaphragm chamber, superior quality materials, and the design of the gage movement.

The temperature murphygage operates on the same mechanical principle as the pressure instrument. As temperature rises, the fluid in the sensing bulb vaporizes to apply pressure on the diaphragm; the movement translates this vapor pressure to a calibrated reading of temperature on the dial. The standard capillary is copper with a PVC armor.